Electric fan heater



Sept; 1959 w. M. COPELAND ETAL 2,904,317

ELECTRIC FAN HEATER Filed July 23, 1956 United States PatentO ELECTRIC FAN HEATER William M. Copeland, Stratford, and Robert W. Mazzacane, Orange, Conn., assignors to General Electric Company, a corporation of New York Application July 23, '1956, Serial No. 599,573 3 Claims. (Cl. 257-306) This invention relates to electric fan heaters, and more particularly to an electric fan heater of the type provided with a thermostat for controlling the heating element and a fan for forcing air out of the heater.

Electric fan heaters with automatic temperature control means for controlling energization of a heating element provide a valuable addition to the heating art, but present a serious problem with respect to reliable thermostats for sensing the room temperature in contrast to the much higher temperature of the air forced out of the heater and the heat reflected, radiated and conducted by the heater.

Accordingly, it is an object of this invention to provide an improved electric fan heater with a thermostat so positioned as to be responsive to room temperature and to be substantially uninfluenced by the temperature of the heater or the air heated by the heater.

In accordance with one aspect of this invention, a fan heater is provided with a casing having front and rear Walls. An air discharge opening is formed in the front wall of the casing and a fan is positioned in the casing adjacent to the discharge opening for forcing heated air out of the discharge opening. A heating element is suitably positioned in the casing and a reflector is positioned between the heating element and the rear wall. A thermostat for controlling the heating element is located be hind the reflector and an air inlet opening is formed in the rear Wall adjacent to the thermostat. By this arrangement, the fan may draw air which is substantially at room temperature from behind the heater, through the opening formed in the rear wall, over the thermostat, and then between the rear wall and the reflector to the fan. Thus, the thermostat is located so as to be responsive to room temperature and may accurately control energization of the heating element in accordance with the room temperature.

Other objects and advantages of this invention will be apparent from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a rear elevational view of my improved electric fan heater;

Fig. 2 is a cross-sectional view taken along line 2--2 of Fig. 1;

Fig. 3 is a schematic diagram of a circuit for use with an improved electric fan heater of this invention.

Referring now to Fig. 2 of the drawing, there is illustrated an electric fan heater having a heating element 1, a casing generally indicated by reference numeral 2, a thermostat 3 located on the casing, and a fan 4 driven by an electric motor 5 for forcing heated air out of the improved fan heater.

The casing comprises generally upstanding front and rear walls 6 and 7, respectively. Rear wall 7 is provided with a generally horizontal portion 8 for mounting thermostat 3. It is preferred that a grill 9 be provided as a guard for an enlarged air inlet opening 10 formed in front wall 6. A heated air discharge opening 11 is also formed in front wall 6 below air inlet opening 10. A

Patented Sept. 15," 1959 front grill 12 which may be formed of a suitable plastic material is mounted on the front wall 6 of the heater in a conventional manner for guarding the heated'air discharge opening 11. A bottom wall 13 suitably connects front wall 6 to rear wall 7. Downwardly extending feet 14 may be connected to the bottom wall of the improved fan heater by means of screws (not shown) or other suitable securing means. A reflector 15 is positioned in the casing between heating element 1 and rear wall 7 for directing heat generally outwardly and upwardly at an angle with respect to the floor upon which the heater may be positioned.

' This improved electric fan heater is uniquely designed so that thermostat 3 is positioned so as to be responsive to the room temperature and to be substantially unaffected by the operation of the heating element. Accordingly, an enlarged opening 16 is formed in the rear wall 7 of the heater for receiving thermostat 3. Thermostat 3 does not completely close openings 16, but is supported in the opening 16 by means of a thermostat cover 17. Thermostat cover 17 may be connected to the upper portion of thermostat 3 in a suitable manner and then thenmostat cover 17 is suitably secured to the curved up per portion of rear wall 7. A knob 18 may be provided for adjusting the setting of thermostat 3 in a manner known in the art. Suitable air inlet openings in the form of louvers may beformed in thermostat cover 17 for allowing air at substantially room temperature to enter the thermostat cover from behind the heater and surround the thermostat so that the thermosta will respond to the room temperature. 7

The improved fan heater is so constructed so that there are three different air streams, each serving a particular purpose. Air is drawn in through the louvers 19 formed in thermostat cover 17 and surrounds the thermostat thus causing it to be responsive to ambient temperatures. This air then flows downwardly over the back of the reflector 15 between the reflector and the rear casing 7 to thereby 'coolrear casing 7. At the same time, the air is heated by contact with the back of reflector 15 and the front of rear wall 7 before it is discharged from the heater by means of fan 4. In this manner, rear wall 7 is maintained at a comfortable temperature and a maximum amount of heat is transferred to this cooling air stream before it is discharged from the heater.

A second air stream commences at air inlet opening 10 in front of the reflector. This air stream moves generally downwardly along the front of the reflector to cool the reflector and surrounds and passes the heating element 1 to pick up heat. A slot 20 is provided between main reflector 15 and a secondary reflector 21. This slot 20 is arranged to prevent direct radiation into a motor chamber 22 and its sides may be adjusted to maintain a perfeot balance of air flow between this second air stream and the other air streams. A third air stream commences at the slots 23 formed in the bottom wall 13 of the heater. This air stream moves upward through the motor housing to help keep the motor cool and is then directed outwardly through grill 12 by fan 4 in the same manner as the other air streams.

Referring now to the circuit diagram of Fig. 3, it is evident that the heating element 1, motor 5, and the thermostat 3 are connected in series with each other. Thermostat 3 is shown as comprising a bimetal blade 24 having a movable contact 25 positioned at the free end thereof for cooperating with a fixed contact 26. Thus, upon an increase in room temperature, bimetal blade 24 will be caused to move upwardly to separate contact 25 from fixed contact 26 to open the switch and interrupt the power supplied to both the motor 5 and the heating element 1.

While there has been shown and described a particular embodiment ,of this invention, it will be obvious to those skilledin the art that various changes and modifications can be made therein without departing from the invention, and therefore, it is aimed in the appended claims to s v l su t a e ta r n ifiw sns s. a l With the true spirit and scopeoftheinvention.

jrWhat we claim as new anddesire to secure by Letters Patentofzthe United States is:

i 1. A fan heater comprising a casing having upstandingfront and rear walls, an air inlet openingformed in said front wall, an air discharge openingformed in front wallbelowsaid air inlet opening, a fan positioned in the bottom poltion-of said casingadjacentto said discharge opening for forcing heated air out of the discharge opening, a heating element positioned in saidcasing, a reflector positioned in said casing between said heating element and said rear wall, a thermostat locatedbehind the reflector for controlling the heating element, and an air inletopening formed in the upper portion of said rear wall adjacent to said thermostat, whereby a first air stream may flow from said air inlet opening formed in the front wall, across the front of said reflector and over said heating element to the fan, and a second, air stream may flow through said air inlet opening in the upper portion of said rear wall around saidthermostat and downwardly between the rear wall and the reflector to the bottom of the casing to maintain the rear wall at a comfortable temperature.

2. A fan heater comprising a casing having upstanding front, rear and bottom walls, anair inlet opening formed in the front wall, an air discharge opening formed in ,said front wall below said air inlet opening, afan positioned in the bottom portion of said casing adjacent to said discharge opening for forcing heated air out of said discharge opening, and an electric motor positioned in said casing for driving said fan, an air inlet opening formed in said bottom wall adjacent to said motor for providing cooling air to saidmotor, a heating element positioned in said casing, a reflector positioned in said casing between said heating element. and said rear wall, a thermostat located behind the reflector for controlling the heating element, and an air inlet opening formed in the upper portion of said rear wall adjacent to said themostat, whereby a first air stream may flow from the air inlet opening formed in the front wall across the front'of said reflector and over said heating element to the fan, a second air stream may flow through said air inlet opening in the upper portion of said rear "wall around said thermostat, and downwardly between the rear wall and the reflector to the bottom of the casing to maintain the rear wall at a comfortable temperature, and a third air stream may flow through said air inlet opening in said bottom wall through said motor to the fan.

3. A fan heater comprising acasing having upstanding front and rear walls, an airinlet opening formed in said front wall, a discharge opening formed in said front wall below said air inlet. opening, a fan positioned inthe bottom portion of said casing adjacent to said discharge opening for forcing heated air out of the discharge opening, a heating element positioned in said casing, a reflector positioned in said casing between said heating element and said rear wall, a thermostat located behind the reflector at the top portion of said casing for controlling the heating element, a cover for said thermostat, an air inlet opening formed in said cover, and an airinlet opening formed in said rear wall adjacent to said thermostat whereby a first air stream may flow from said air inlet opening formed in said front wall, across the front of said reflector and over said heating element to the fan, and the second air stream may flow through the air inlet opening formed in said cover through the air inlet opening formed in said rear wall around said thermostat and downwardly between the rear wall and the reflector to the bottom of the casing to maintain the rear wall at a comfortable temperature.

References Cited in the file of this patent UNITED STATES PATENTS 1,948,759 Hoffman Feb. 27, 1934 1,986,350 Logan Jan. 1, 1935 2,135,461 Woolley Nov. 1, 1938 2,166,635 Locke July 18, 1939 2,498,157 Farr Feb. 21, 1950 2,765,393 Theisen Oct. 2, 1956 FOREIGN PATENTS 381,709 Great Britain Oct. 13, 1932 456,461 Great .Britain June 17, 1936 939,897 Germany .Mar. 8, 1956 

